Shaquille O’Neal shook his head, frowned slightly and shrugged when asked whether he would play at the Athens Olympics.

“I’m still not sure,” the Los Angeles Lakers’ center said.

He’s not the only one.

There are more questions than answers right now for the USA Basketball selection committee, with only six players considered locks to show up in Greece: Jermaine O’Neal, Tim Duncan, Allen Iverson, Tracy McGrady, Mike Bibby and Richard Jefferson.

Among those wavering are Jason Kidd, Karl Malone, Elton Brand, Ray Allen and Kevin Garnett.

Vince Carter already ruled himself out, and Kobe Bryant’s availability hinges on the schedule for his sexual assault trial in Colorado.

“It’s not troubling, but it is what it is,” Stu Jackson, chairman of the USA Basketball selection committee, said Tuesday. “In a perfect world, we’d like to have a roster in place by May 1. But given the circumstances, that seems unlikely.”

Among the reasons for the hedging are injuries, fears of terrorism, and family plans, including a wedding and a birth.

Shaquille O’Neal said his participation in the Aug. 13-29 Olympics would depend largely on how far the Lakers advanced in the NBA playoffs, and Minnesota’s Garnett sent a similar message to USA Basketball officials.

Bryant, O’Neal’s teammate with the Lakers, is accused of sexually assaulting a hotel employee in Colorado. He did not have to surrender his passport when he posted bail, with the only requirement on overseas travel being that he inform the court.

Kidd has said his participation would depend on his left knee, which could require surgery after the NBA playoffs. Malone and Brand also have injury concerns, and Malone has indicated he was not enthusiastic about traveling to cities where anti-American sentiment had grown.

These days, the level of competition no longer tilts heavily toward the Americans — even at full strength. A U.S. team of NBA players lost to Argentina, Yugoslavia and Spain at the 2002 World Championships, and the American team that won the Olympic gold medal in Sydney needed a last-second miss by Lithuania to survive its semifinal game.